Under the Bag (based on my understanding of cryptics, but not quite how cryptics actually work)

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Across
  1. 2. interwoven share pal 4/4
  2. 4. dull person with heavy weight 8
  3. 5. copyright shotgun pellets 3/5
  4. 8. twirling sea accent 9
  5. 9. ball of fire swimmer 8
  6. 12. gyrating min. [is] 6
  7. 15. an orifice in metal 8
  8. 17. sea mouth 5
  9. 18. officially registered in murder 5
  10. 21. mash'd cheap loops 11
Down
  1. 1. late, scored letters 11
  2. 3. curve between two bugs 9
  3. 6. lookin', but you interrupted 3/6
  4. 7. forgot reservations to barbecue on 4
  5. 10. narrow beam armed? 3/6
  6. 11. missplaced end of prayer with single 7
  7. 13. quiet curve-so I heard 5
  8. 14. eight, shove cut short 7
  9. 15. swirled but you can't lick it 5
  10. 16. copyright heroin 3/5
  11. 19. bishop inside game judge 4
  12. 20. largest living creature 4/5